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A133974 Home primes whose homeliness is 10. 12
77773, 312619, 359929, 364627, 374531, 749711, 771941, 1355021, 1389281, 1929311, 1991153, 2336263, 2337547, 2339929, 2373823, 2389853, 2397127, 3137993, 3139547, 3139733, 3139907, 3235471, 3312539, 3313631, 3316661 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number of terms < 10^n: 0, 0, 0, 0, 1, 7, 82, ....

LINKS

Table of n, a(n) for n=1..25.

MATHEMATICA

lst = {}; f[n_] := FromDigits@ Flatten[ IntegerDigits@ Table[ #[[1]], {#[[2]]}] & /@ FactorInteger@n, 2]; h[n_] := NestWhileList[f@# &, n, !PrimeQ@# &, 1, 28]; Do[p = h[n][[ -1]]; If[ PrimeQ@p && p < 10^7 && p != n, Print[{n, p}]; AppendTo[lst, p]], {n, 2, 1000}];

d = 10 - 2; lsu = {}; Do[ If[ lst[[n]] == lst[[n + d]] && lst[[n - 1]] != lst[[n]] && lst[[n]] != lst[[n + d + 1]], AppendTo[lsu, lst[[n]]]], {n, 188004 - d - 1}]; Take[Union@ lsu, 35]

CROSSREFS

Cf. A037274, A118756, A133973, A133956, A000014, A133958, A133960, A133962, A133964, A133966, A133968, A133970, A133972, A133976, A133978.

Sequence in context: A087026 A133971 A133973 * A321235 A266967 A061528

Adjacent sequences:  A133971 A133972 A133973 * A133975 A133976 A133977

KEYWORD

nonn,base

AUTHOR

Robert G. Wilson v, Sep 30 2007

STATUS

approved

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Last modified September 26 11:48 EDT 2020. Contains 337371 sequences. (Running on oeis4.)